Rhinitis and dry cough. The virus damages the mucosa of the upper respiratory tract causing its inflammation. Organism produces a special kind of protein to combat them and plenty of liquid is released from the damaged capillaries. In this case, the nasal discharge is transparent but if the leukocytes start fighting the virus the color changes to yellow-green. Cough appears as a consequence of the larynx swelling. If the inflammation spreads to the vocal cords, the voice may disappear.